In U.S. Pat. Nos. 3,575,999, 3,936,470 and Belg. Pat. No. 835,579 there are described a number of 1-(1,3-dioxolan-2-yl-methyl)-1H-imidazoles and 1H-1,2,4-triazoles having antifungal and antibacterial properties. The compounds of this invention differ from the foregoing essentially by the nature of the complex substituent group present in the 4-position of the dioxolane moiety.